> The general rule for precision electronics is that you want to avoid anything that needs high absolute accuracy (because such things get expensive fast even as discrete components) and instead rely on accurate ratios between parameters, matched pairs of components and inaccurate, but long term stable parameters that can be calibrated out.

The omitted serial comma made that really hard to parse for me. In case it did for anyone else, I think that it's:

> (accurate ratios between parameters) and (matched pairs of components) and (inaccurate, but long-term stable, parameters that can be calibrated out).